This invention relates to the field of polymer processing where a specific polymer and additives have been blended to form a composition that helps in maintaining a constant coefficient of friction in Polyethylene (PE) based films.
Polyethylene due to its chemical composition is non polar in nature. Polyethylene also due to its specific chemical characteristics is a material of choice in the flexible packaging industry and is used to make bags, containers and consumer household products. However, polyethylene has a very high coefficient of friction and the same results in issues related to conversion for a film converter. Additives such as Fatty Acid. Amides (Erucamide, Oleamide etc.) are commonly added to the Polyethylene film so as to reduce the Coefficient of Friction and help with ease of conversion. These additives are polar in nature and because of inherent incompatibility with the nonpolar PE matrix, bloom to the surface as a function of time. Whereas, the presence of slip on the surface helps with the conversion process by lowering the COF; the same also causes problems in printing and lamination. Variation of COF and inadequate printing are some of the most common issues experienced by converters.
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